Not a specialist, just from what I heard: There are two things that make it work. First they are not really "independent" like the title says. They sync with the grid frequency. If the grid is down they shut off for safety. The other reason it works is that the grid power inside the home is just what you get as incoming power 〜230V. For example, I think in the US you get 240V or so delivered to your house, but 120V from the plug.
Very nice! In Tokyo we had this mural some parts were animated using screens in the wall.
https://www.teamlab.art/w/skytreemural/tokyoskytree/
The TOKYO SKYTREE mural | teamLab
The Tokyo Skytree mural is located on the Fourth floor of Tokyo Skytree®. Ten monitors are embedded in the wall, forming a seamless picture; the images shown on the monitors are digital animation.In traditional Japanese art, there is no center of focus, there is no fixed time frame, and a vast amoun...
teamLabOpenTTD | News | Changes to OpenTTD distribution on Steam
An open source simulator based on the classic game Transport Tycoon Deluxe. It attempts to mimic the original game as closely as possible while extending it with new features.